EV cars, would you, wouldn't you?

[gazchap]

300bhp/ton said:

Interesting. I assume it needs some sort of internet connectivity to do this however? Does it have an integrated phone system or some other mechanism to do this?

It has an integrated telematics system, yes - it uses the mobile data network to allow you to remote control certain functions of the car (e.g. you can tell it to start charging at any time (provided it's plugged in, of course) and also activate climate control, and see the current charge level.)

It can also e-mail you when a charge completes, it has an internal database of charging stations which it keeps up to date for you (including live availability in some instances, although this isn't particularly reliable) and you can use a Nissan-provided route planner to plan a journey, including charging stops if necessary, and send that directly to the car's sat nav, all from the comfort of your home web browser.

For me, the most beneficial feature is that with the car plugged in I have it set to start charging at whatever time of the morning it needs to to ensure that it finishes charging at 7.30am (so that the car is at 100% battery charge for as short a time as possible) and then at 8.10am every morning (because I've told it I leave at 8.20) it will preheat the car for me, defrost the windscreen, and also heat up the steering wheel so that everything is toasty warm when I get in - which of course means that I don't need to run the heater as much on the journey itself, thus saving battery that way too.

It takes a bit of setting up, granted, but the convenience of the whole package far outstrips the equivalent ICE vehicle for me. I've done 1,200 miles in the last 25 days and I'm beginning to forget what it feels like to drive to a petrol station and fill up that way.

[gazchap]

300bhp/ton said:

It must still use power, and it's not as if you are sat completely motionless, most heavy traffic is stop start, crawl along. Today would have meant side lights (or more), wipers, blowers and the stereo on.

The car has an infoscreen on the head unit which shows live energy usage. When at a standstill, or even in stop-start traffic, power usage is so low it barely registers on the "power meter" - and it separates out usage for the climate control so you can see what effect that has (FWIW, hardly any effect at all)

Wipers and the stereo use barely any power at all, and switching the lights on pushes energy usage up by about 0.2 kW - so with approx. 20kWh of usable battery (conservative estimate) you could sit at a standstill with everything on for a bloody long time before it posed a problem.

True - you could do that with an ICE car too, but you'd have to keep the engine running which would obviously burn fuel and have all the noise, odour and vibrations to go along with it.

(don't get me wrong incidentally - I've not given up the ICE yet, I still have my Celica and use it as my "fun car" - but make no bones about it, for everyday travel I'm definitely an EV convert)

[Tickle]

Yes, no problem with using one for my small commute or the family car if range is not an issue.

For the weekend fun car, nope; not at all.

[Willy Nilly]

Tickle said:

For the weekend fun car, nope; not at all.

Electric motor have 100% torque at zero rpm and rev and rev. The only issues are range, weight of the batteries and cost.

[mattlad]

What's to stop some mischievous, cretinous oik from creeping onto your drive one night and unplugging your EV?

[otolith]

300bhp/ton said:

I have no idea what affect such driving conditions would have on an EV, but driving 35 miles on clear roads with an average speed of say 40-50mph+, is likely to be vastly different to the same journey with an average speed of say 15mph.

I suspect that an EV has a very different energy usage against speed curve to an ICE car.

These are for Tesla Model S and Roadster;

(consumption, analogous to gallons per mile)



(range, analogous to miles per gallon)



These are some miles per gallon curves for ICE cars;

[kambites]

I'm astonished at that peak at 70ish in the Honda. There's either something very odd going on with the engine map there or some clever step change in aerodynamics at around that speed (or both).

[ORD]

That's the kicker for an EV as a car for long journeys - range drops of really badly at motorway speeds. Contrast powerful petrols and diesels, many of which seem to burn no more fuel at 70+ than at 40. The graphs back that up. I would not see driving at less than 70mph on the motorway as a reasonable compromise. Motorway driving is utterly horrendously dull, and I won't drive 1mph below what is safe and legal in the conditions!

[otolith]

kambites said:

I'm astonished at that peak at 70ish in the Honda. There's either something very odd going on with the engine map there or some clever step change in aerodynamics at around that speed (or both).

Or there is a dip earlier.

[kambites]

ORD said:

That's the kicker for an EV as a car for long journeys - range drops of really badly at motorway speeds.

To be fair, that's because EV drive efficiency is constantly good whereas ICEs are a bit rubbish at 70 and absolutely appalling at 20. The problem with EVs for long trips is that they simply can't store anywhere near as much energy as a liquid fuelled car (yet) and they aren't enough more efficient at higher speeds to counter that.

Still the point ends up being the same; if you're one of the (relatively few) people who do regularly journeys of hundreds of miles, current EVs don't work.

Edited by kambites on Monday 5th October 19:22

[kambites]

otolith said:

kambites said:

I'm astonished at that peak at 70ish in the Honda. There's either something very odd going on with the engine map there or some clever step change in aerodynamics at around that speed (or both).

Or there is a dip earlier.

Maybe but I didn't think any car had peak economy at over about 50mph. Very interesting.

[otolith]

kambites said:

Maybe but I didn't think any car had peak economy at over about 50mph. Very interesting.

I'd want to see error bars on the graph before I got too excited...

[Tickle]

Willy Nilly said:

Tickle said:

For the weekend fun car, nope; not at all.

Electric motor have 100% torque at zero rpm and rev and rev. The only issues are range, weight of the batteries and cost.

They do seem to be heavy, not something that I want in a fun car. Torque is not really a property in an engines delivery that is high on my priorities either from my weekend car, I prefer rev hungry engines with short gear ratios that make you work.

[DaveCWK]

I would have an electric car, in theory.

Not for many years though. Too expensive, too compromised, not mature enough right now.

[kambites]

Tickle said:

They do seem to be heavy

Very heavy compared to storing the same amount of energy in a fuel tank, certainly.

[ORD]

kambites said:

otolith said:

kambites said:

I'm astonished at that peak at 70ish in the Honda. There's either something very odd going on with the engine map there or some clever step change in aerodynamics at around that speed (or both).

Or there is a dip earlier.

Maybe but I didn't think any car had peak economy at over about 50mph. Very interesting.

A lot depends on gearing and slipperiness, doesn't it? I have found that powerful cars don't burn much more fuel at 70 than 50, whereas less powerful cars really struggle.

An important point about EVs - we have to think about what they are actually going to replace. Eco petrol and diesel cars. 4 cyl, horrible, dull, slow crapboxes that are a complete drudgery to drive, if not actively unpleasant.

You would have to pull my 911 from my dead hands to replace it with an EV, but I can't think of many 2015 petrol or diesel cars that I have driven that would be made worse by being EVs. No brake feel anyway. No steering feel anyway. Horrible slushy autos or manuals ruined by clutch delay valves and unresponsive throttles.

If everyone was popping to the shops in 993s and heel-and-toeing up to roundabouts, EVs would be a cause for despair. Truth is that they are dull ecoboxes that will replace even duller ecoboxes. At least some of them are fast!

[SidewaysSi]

No, not my sort of thing. I tend not to buy white goods new cars though.

[kambites]

ORD said:

A lot depends on gearing and slipperiness, doesn't it? I have found that powerful cars don't burn much more fuel at 70 than 50, whereas less powerful cars really struggle.

Perhaps it depends on how you define "powerful" but taking the OH's Octavia as a typical moderately power family car, on a flat straight road it does about 45mpg at 50mph; about 40mpg at 70mph; and about 35mpg at 80mph. Once you get to 90mph it's under 30mpg and at 100+ I suspect it'd be in the low 20s/high teens.

My car is even more extreme. It's most economical at about 35mph because the aerodynamics are so appalling.

Edited by kambites on Monday 5th October 19:31

[kambites]

ORD said:

Truth is that they are dull ecoboxes that will replace even duller ecoboxes. At least some of them are fast!

Indeed, which means they will probably be an improvement compared to the 90+% of cars currently on the road.

You'd have to pry my Elise from my dead hands to get me to replace it with a modern 911, let alone an EV.

Edited by kambites on Monday 5th October 19:32

[ORD]

200bhp/ton

In seriousness, I think the difference is quite substantial in my wife's 320i (6 speed manual); but it's negligible in a Porker with the PDK box (very long 7th gear).